Women are more likely to be addicted to smoking - here's why

Women struggle to quit smoking more than men (Picture: Getty)

The female sex hormone oestrogenmay be the reason women are more likely to be addicted to nicotinethan men – potentially opening new avenues for treatment.

Data from a new study suggests that women generally become dependent on nicotine after less exposure than men, and then struggle more with quitting.

Researchers from the University of Kentucky in the US decided to investigate this disparity among smokers and soon discovered that it may have something to do with hormones.

The team, led by PhD student Sally Pauss, found that oestrogen induces the expression of olfactomedins, a type of protein involved in the brain’s processing of reward and addiction.

Nicotine has been proven to suppress olfactomedins – which means the interaction between oestrogen, nicotine and olfactomedin may be the reason women struggle more with addiction.

Ms Pauss said she hopes the new revelations, published in the journal American Society for Biochemistry and Molecular Biology, will open doors for new treatment possibilities which will hopefully help women stop smoking.

She said: ‘Our work hoped to understand what makes women more susceptible to nicotine use disorder, in order to reduce the gender disparity in treating addiction to nicotine.

‘Our findings have the potential to better the lives and health of women struggling with substance misuse.

‘If we can confirm that oestrogen drives nicotine seeking and consumption through olfactomedins, we can design drugs that might block that effect by targeting the altered pathways.

‘Hopefully, these drugs would make it easier for women to quit nicotine.’

The research team studied genes that react to oestrogen to see which ones have a hormone function in the brain.

They found that only one class of genes met this criteria – those coding for olfactomedins – which prompted them to perform a series of tests to better understand the interactions between olfactomedins, oestrogen, and nicotine.

Results of the tests, conducted with human uterine cells and rats, suggested that oestrogen’s activation of olfactomedins – which is suppressed when nicotine is present – might serve as ‘a feedback loop’ for driving nicotine addiction processes.

‘It is possible it does this by activating areas of the brain’s reward circuitry,’ Ms Pauss explained.

Now the team wants to conduct further studies that definitively determine whether oestrogen contributes to a nicotine addiction.

Researchers also want to better understand how olfactomedin-regulated signalling pathways work, particularly in relation to how they drive nicotine consumption.

Ms Pauss said that this knowledge will be helpful for women everywhere, but particularly for those taking oestrogen in the form of the contraceptive pill or via hormone replacement therapy.

‘This is because, if our findings are proven, these things could increase a woman’s risk of becoming addicted to nicotine,’ she said.

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